A patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device and method

Abstract

The present invention discloses a patch-type piezoelectric-driven longitudinal-torsional composite rotary feeding device and method, comprising a piezoelectric transducer, a feed tray, and a base. The piezoelectric transducer comprises a metal substrate and first to fourth drive units, each of which is disposed on the four sides of the piezoelectric transducer's vibrating portion, one-to-one, and comprises first to fifth piezoelectric ceramic discs. During operation, the transducer's first-order longitudinal vibration mode and first-order torsional vibration mode are excited, respectively, and superimposed to excite a longitudinal-torsional composite mode of the transducer, causing the feed tray to vibrate in both torsional and vertical directions, thereby rotating the material within the feed tray and discharging it from the feed tray's material outlet. The present invention has a simple structure, is easy to process and assemble, and offers excellent driving performance.

Description

Technical Field

[0001] The present invention relates to the fields of piezoelectric feeders, material conveying and micro-particle transportation, and in particular to a patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device and method. Background Art

[0002] The vibrating material conveying device is a commonly used feeding equipment that can realize one-way directional conveying of materials. It has important application value in modern automated production, micro parts processing, semiconductor packaging and testing and other fields.

[0003] Vibratory material conveying devices can be categorized as electromagnetic and piezoelectric, depending on the source of vibration. Feeding devices using electromagnets as a driving force suffer from drawbacks such as high noise levels, low energy conversion efficiency, and unsuitability for precision material conveying. With the advancement of piezoelectric technology, new actuators using piezoelectric materials as a driving force are attracting increasing research interest.

[0004] Based on the material conveying method, piezoelectric vibratory material conveying devices can be categorized as linear or rotary. In 1977, researchers at Japan Tokushige Ceramics Co., Ltd. first proposed a linear piezoelectric vibratory feeder using rectangular piezoelectric ceramic discs as a driving source. The linear piezoelectric vibratory feeder developed by Japanese researchers primarily consists of a base, a piezoelectric vibrator, a spring plate, and a top plate. The operating principle is that when the piezoelectric vibrator is excited by an alternating excitation signal, the inverse piezoelectric effect causes the spring plate to flex reciprocally under the piezoelectric ceramic excitation, inducing elliptical motion in the top plate, thereby conveying the material. Later, Japanese researchers developed a rotary material conveyor with the same operating principle. Again, using a piezoelectric ceramic disc as a driving source, the spring plate flexes reciprocally, inducing horizontal and vertical vibration components in the top plate. These horizontal and vertical vibration components enable material transport. However, due to its fixed structure and the inability to adjust the spring disc angle, this rotary material conveyor can only transport materials in one direction. Furthermore, since the vertical and horizontal components of the feed tray cannot be adjusted, it can only convey a single type of material. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device and method in response to the defects involved in the background technology.

[0006] The present invention adopts the following technical solutions to solve the above technical problems:

[0007] A patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device, comprising a piezoelectric transducer, a feeding tray and a base;

[0008] The piezoelectric transducer includes a metal substrate and first to fourth driving units;

[0009] The metal base includes a vibrating portion and a connecting portion, wherein the vibrating portion is a regular square prism arranged vertically; the connecting portion is a regular square prism having the same shape as the upper end surface of the vibrating portion, the lower bottom surface of the connecting portion and the upper end surface of the regular square prism correspondingly and coaxially connected, and the area of ​​the upper bottom surface of the connecting portion is smaller than the area of ​​the lower bottom surface;

[0010] The first to fourth driving units are arranged on the four side surfaces of the vibration part in a one-to-one correspondence, and each includes a first to a fifth piezoelectric ceramic sheet; the fifth piezoelectric ceramic sheet is arranged at the center of the side surface of the vibration part corresponding to the driving unit in which it is located; the first and second piezoelectric ceramic sheets are arranged above the fifth piezoelectric ceramic sheet at the same height, and the third and fourth piezoelectric ceramic sheets are arranged below the fifth piezoelectric ceramic sheet at the same height, the first and third piezoelectric ceramic sheets are arranged symmetrically with respect to the fifth piezoelectric ceramic sheet, and the second and fourth piezoelectric ceramic sheets are arranged symmetrically with respect to the fifth piezoelectric ceramic sheet; the first to fifth piezoelectric ceramic sheets are all rectangular and are polarized along their thickness direction, wherein the polarization directions of the first and second piezoelectric ceramic sheets are opposite, the polarization directions of the third and fourth piezoelectric ceramic sheets are opposite, and the polarization directions of the first and third piezoelectric ceramic sheets are opposite;

[0011] The polarization directions of the fifth piezoelectric ceramic pieces in the first to fourth driving units are all inward or outward;

[0012] The material tray is in the shape of a disk, with a material outlet provided on its side wall and a groove having the same shape as the connecting portion provided at the center of its lower bottom surface;

[0013] The connecting portion of the metal base of the piezoelectric transducer is fixedly connected to the groove in the center of the lower bottom surface of the tray, and the lower end of the vibration portion of the metal base of the piezoelectric transducer is fixedly connected to the base.

[0014] As a further optimization solution of the patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device of the present invention, the first to fifth piezoelectric ceramic sheets in the first to fourth driving units are all adhered to the metal substrate by epoxy resin glue.

[0015] As a further optimization solution of the patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device of the present invention, a through hole is provided in the center of the material tray, a threaded blind hole is provided in the center of the upper end face of the connecting part, and the connecting part and the material tray are fixedly connected by bolt threads.

[0016] As a further optimization scheme of the patch-type piezoelectric-driven longitudinal-torsional composite rotary feeding device of the present invention, the base is a square plate, the center of which is provided with a groove that matches the lower end face of the vibration part, and the center of the base groove is provided with a through hole; the center of the lower end face of the vibration part is provided with a threaded blind hole; the vibration part and the base are fixedly connected by bolt threads.

[0017] The present invention also discloses a working method of the patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device, comprising the following steps:

[0018] A simple harmonic excitation voltage signal U1 is applied simultaneously to the fifth piezoelectric ceramic piece of the first to fourth piezoelectric drive units, and a simple harmonic excitation voltage signal U2 is applied simultaneously to the first to fourth piezoelectric ceramic pieces of the first to fourth piezoelectric drive units. The frequencies of U1 and U2 are the same and the phase difference is 0. U1 can excite the first-order longitudinal vibration mode of the transducer, and U2 can excite the first-order torsional vibration mode of the transducer. The superposition of longitudinal vibration and torsional vibration can excite the longitudinal-torsional composite mode of the transducer, so that the material tray vibrates in the torsional direction and the vertical direction. The material placed in the material tray produces translational and vertical motion around the axis of the disk under the action of friction. When the material moves to the top, the elastic potential energy of the first spring piece in each drive unit reaches the maximum value, the material tray starts to move back, and the material falls in a parabola due to inertia. During the periodic vibration process, the material rotates in the material tray and is discharged from the material outlet of the material tray.

[0019] If the material needs to rotate in the opposite direction, adjust the phase difference between U1 and U2 to 180°;

[0020] By adjusting the ratio of the signal voltages of U1 and U2, the ratio of horizontal vibration to vertical vibration on the tray can be adjusted, thereby adjusting the vibration height and transportation speed of the material in the tray.

[0021] Compared with the prior art, the present invention adopts the above technical solution and has the following technical effects:

[0022] 1. The present invention separately excites the first-order longitudinal vibration and first-order torsional vibration of the piezoelectric transducer, achieving rotational transportation of materials through longitudinal and torsional composite vibration, with the advantages of simple structure and easy control.

[0023] 2. By adjusting the voltage ratio of signals U1 and U2, the amplitude of longitudinal vibration and torsional vibration can be adjusted respectively, thereby adjusting the ratio of horizontal vibration to vertical vibration on the tray, making the device suitable for transporting different materials;

[0024] 3. By adjusting the phases of the two-phase excitation signals U1 and U2 to be the same or opposite, the material can be driven to move in the forward and reverse directions. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the present invention;

[0026] Figure 2 It is a structural schematic diagram of the piezoelectric transducer in the present invention;

[0027] Figure 3 It is a structural schematic diagram of the material tray in the present invention;

[0028] Figure 4 It is a structural schematic diagram of the base in the present invention;

[0029] Figure 5 is a schematic diagram of a method for applying an electrical signal to a piezoelectric transducer in the present invention;

[0030] Figure 6 It is a simulation comparison diagram of the first-order longitudinal vibration and the first-order torsional vibration in the present invention.

[0031] 1-base, 2-piezoelectric transducer, 3-material tray, 4-connecting part, 5-vibrating part, 6-first piezoelectric ceramic sheet, 7-second piezoelectric ceramic sheet, 8-third piezoelectric ceramic sheet, 9-fourth piezoelectric ceramic sheet, 10-fifth piezoelectric ceramic sheet. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings:

[0033] The present invention can be implemented in many different forms and should not be considered to be limited to the embodiments described herein. On the contrary, these embodiments are provided to make this disclosure thorough and complete and will fully convey the scope of the invention to those skilled in the art. In the accompanying drawings, components are enlarged for clarity.

[0034] It should be understood that although the terms first, second, third, etc. may be used herein to describe various elements, components, and / or parts, these elements, components, and / or parts are not limited by these terms. These terms are merely used to distinguish elements, components, and / or parts from each other. Therefore, the first element, component, and / or part discussed below can become the second element, component, or part without departing from the teachings of the present invention.

[0035] like Figure 1 As shown, the present invention discloses a patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device, comprising a piezoelectric transducer, a feeding tray and a base;

[0036] like Figure 2 As shown, the piezoelectric transducer includes a metal substrate and first to fourth driving units;

[0037] The metal base includes a vibrating portion and a connecting portion, wherein the vibrating portion is a regular square prism arranged vertically; the connecting portion is a regular square prism having the same shape as the upper end surface of the vibrating portion, the lower bottom surface of the connecting portion and the upper end surface of the regular square prism correspondingly and coaxially connected, and the area of ​​the upper bottom surface of the connecting portion is smaller than the area of ​​the lower bottom surface;

[0038] The first to fourth driving units are arranged on the four side surfaces of the vibration part in a one-to-one correspondence, and each includes a first to a fifth piezoelectric ceramic sheet; the fifth piezoelectric ceramic sheet is arranged at the center of the side surface of the vibration part corresponding to the driving unit in which it is located; the first and second piezoelectric ceramic sheets are arranged above the fifth piezoelectric ceramic sheet at the same height, and the third and fourth piezoelectric ceramic sheets are arranged below the fifth piezoelectric ceramic sheet at the same height, the first and third piezoelectric ceramic sheets are arranged symmetrically with respect to the fifth piezoelectric ceramic sheet, and the second and fourth piezoelectric ceramic sheets are arranged symmetrically with respect to the fifth piezoelectric ceramic sheet; the first to fifth piezoelectric ceramic sheets are all rectangular and are polarized along their thickness direction, wherein the polarization directions of the first and second piezoelectric ceramic sheets are opposite, the polarization directions of the third and fourth piezoelectric ceramic sheets are opposite, and the polarization directions of the first and third piezoelectric ceramic sheets are opposite;

[0039] The polarization directions of the fifth piezoelectric ceramic pieces in the first to fourth driving units are all inward or outward;

[0040] like Figure 3 As shown, the material tray is in the shape of a disk, a material outlet is provided on its side wall, and a groove with the same shape as the connecting portion is provided at the center of the lower bottom surface;

[0041] The connecting portion of the metal base of the piezoelectric transducer is fixedly connected to the groove in the center of the lower bottom surface of the tray, and the lower end of the vibration portion of the metal base of the piezoelectric transducer is fixedly connected to the base.

[0042] A through hole is provided in the center of the material tray, a threaded blind hole is provided in the center of the upper end surface of the connecting portion, and the connecting portion and the material tray are fixedly connected by bolt threads.

[0043] The first to fifth piezoelectric ceramic sheets in the first to fourth driving units are all adhered to the metal substrate by epoxy resin glue.

[0044] like Figure 5 As shown, the base is a square plate, the center of which is provided with a groove that matches the lower end surface of the vibration part, and the center of the base groove is provided with a through hole; the center of the lower end surface of the vibration part is provided with a threaded blind hole; the vibration part and the base are fixedly connected by bolt threads.

[0045] The present invention also discloses a working method of the patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device, comprising the following steps:

[0046] like Figure 6As shown, a simple harmonic excitation voltage signal U1 is applied simultaneously to the fifth piezoelectric ceramic piece of the first to fourth piezoelectric drive units, and a simple harmonic excitation voltage signal U2 is applied simultaneously to the first to fourth piezoelectric ceramic pieces of the first to fourth piezoelectric drive units. The frequencies of U1 and U2 are the same and the phase difference is 0. U1 can excite the first-order longitudinal vibration mode of the transducer, and U2 can excite the first-order torsional vibration mode of the transducer. The superposition of longitudinal vibration and torsional vibration can excite the longitudinal-torsional composite mode of the transducer, so that the material tray vibrates in the torsional direction and the vertical direction. The material placed in the material tray generates translational and vertical motion around the axis of the disk under the action of friction. When the material moves to the top, the elastic potential energy of the first spring piece in each drive unit reaches the maximum value, the material tray starts to move back, and the material falls in a parabola due to inertia. During the periodic vibration process, the material rotates in the material tray and is discharged from the material outlet of the material tray.

[0047] If the material needs to rotate in the opposite direction, adjust the phase difference between U1 and U2 to 180°;

[0048] By adjusting the ratio of the signal voltages of U1 and U2, the ratio of horizontal vibration to vertical vibration on the tray can be adjusted, thereby adjusting the vibration height and transportation speed of the material in the tray.

[0049] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art in the art to which this invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and, unless defined as such, will not be interpreted in an idealized or overly formal sense.

[0050] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device, characterized in that: Contains piezoelectric transducer, tray and base; The piezoelectric transducer includes a metal substrate and first to fourth driving units; The metal base includes a vibrating portion and a connecting portion, wherein the vibrating portion is a vertically arranged regular square prism; the connecting portion is a regular square pyramid having the same shape as the upper end surface of the vibrating portion, the lower bottom surface of the connecting portion and the upper end surface of the regular square prism correspondingly and coaxially connected, and the area of ​​the upper bottom surface of the connecting portion is smaller than the area of ​​the lower bottom surface; The first to fourth driving units are arranged on the four side surfaces of the vibration part in a one-to-one correspondence, and each includes a first to a fifth piezoelectric ceramic sheet; the fifth piezoelectric ceramic sheet is arranged at the center of the side surface of the vibration part corresponding to the driving unit in which it is located; the first and second piezoelectric ceramic sheets are arranged above the fifth piezoelectric ceramic sheet at the same height, and the third and fourth piezoelectric ceramic sheets are arranged below the fifth piezoelectric ceramic sheet at the same height, the first and third piezoelectric ceramic sheets are arranged symmetrically with respect to the fifth piezoelectric ceramic sheet, and the second and fourth piezoelectric ceramic sheets are arranged symmetrically with respect to the fifth piezoelectric ceramic sheet; the first to fifth piezoelectric ceramic sheets are all rectangular and are polarized along their thickness direction, wherein the polarization directions of the first and second piezoelectric ceramic sheets are opposite, the polarization directions of the third and fourth piezoelectric ceramic sheets are opposite, and the polarization directions of the first and third piezoelectric ceramic sheets are opposite; The polarization directions of the fifth piezoelectric ceramic pieces in the first to fourth driving units are all inward or outward; The material tray is in the shape of a disk, with a material outlet provided on its side wall and a groove having the same shape as the connecting portion provided at the center of its lower bottom surface; The connecting portion of the metal base of the piezoelectric transducer is fixedly connected to the groove in the center of the lower bottom surface of the tray, and the lower end of the vibration portion of the metal base of the piezoelectric transducer is fixedly connected to the base.

2. The patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device according to claim 1, characterized in that: The first to fifth piezoelectric ceramic sheets in the first to fourth driving units are all adhered to the metal substrate by epoxy resin glue.

3. The patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device according to claim 1, characterized in that: A through hole is provided in the center of the material tray, a threaded blind hole is provided in the center of the upper end surface of the connecting portion, and the connecting portion and the material tray are fixedly connected by bolt threads.

4. The patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device according to claim 1, characterized in that: The base is a square plate, the center of which is provided with a groove that matches the lower end surface of the vibration part, and the center of the base groove is provided with a through hole; the center of the lower end surface of the vibration part is provided with a threaded blind hole; the vibration part and the base are fixedly connected by bolt threads.

5. The working method of the patch-type piezoelectric driven longitudinal-torsional composite rotary feeding device according to claim 1, characterized in that: The following steps are involved: A simple harmonic excitation voltage signal U1 is applied simultaneously to the fifth piezoelectric ceramic piece of the first to fourth drive units, and a simple harmonic excitation voltage signal U2 is applied simultaneously to the first to fourth piezoelectric ceramic pieces of the first to fourth drive units. The frequencies of U1 and U2 are the same and the phase difference is 0. U1 can excite the first-order longitudinal vibration mode of the transducer, and U2 can excite the first-order torsional vibration mode of the transducer. The superposition of longitudinal vibration and torsional vibration can excite the longitudinal-torsional composite mode of the transducer, so that the material tray vibrates in the torsional direction and the vertical direction. The material placed in the material tray generates translational and vertical motion around the axis of the disk under the action of friction. When the material moves to the top, the material tray starts to move back, and the material falls in a parabola due to inertia. During the periodic vibration process, the material rotates in the material tray and is output from the material outlet of the material tray. If the material needs to rotate in the opposite direction, adjust the phase difference between U1 and U2 to 180°; By adjusting the ratio of the signal voltages of U1 and U2, the ratio of horizontal vibration to vertical vibration on the tray can be adjusted, thereby adjusting the vibration height and transportation speed of the material in the tray.

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